Clearly, those without it will be unable to buy or sell any kind of goods. Either it is a currency, or a governing mechanism for the use of a currency. In other words, it is about participation in the world’s system at that point in time. It’s about money and its use. The placement of the mark—the forehead and the right hand—denotes being owned by the world system.

Some of our Lord’s most severe teachings were regarding dependence upon money. For the rich young ruler, he had everything in place—he was apostolic material. What our Lord offered him was a place as one of His disciples who were to become the Apostles in the 12 or the 70. But for him, it costs too much, he could not afford it, it was just too expensive. He counted the cost, and could not pay it even though he had it.

https://orthodoxreflections.com/decrypting-the-mark-of-the-beast/